Brian Monteith is a Scottish public relations consultant, politician and commentator, and is the policy director of ThinkScotland.org. He was a Conservative and Unionist Member of the Scottish Parliament between 1999 and 2007.

Undoubtedly the most important year of David Cameron’s premiership has arrived. 2014 not only presents really testing problems for his policy towards the European Union, an issue that would be challenging enough whatever his stance, without the added complication of the potentially embarrassing European Parliament elections – and it also offers up the Scottish independence referendum. The son of a Scot and a devout unionist, Cameron will not want to go down as the Prime Minister who presided over the break-up of the United Kingdom as we know it.

The current political betting of [7-1 on at Paddypower] for a No result reflects the consistent lead that the No campaign has had since serious polling started after the SNP’s famous Scottish Parliament victory in 2011 that ensured a referendum would take place during its second parliamentary term that will end in 2016. Despite all sorts of attempts to give the Yes campaign traction, the most recent being the launch of the Scottish Government’s White Paper late last year, there has been very little shift in the polling that gives the unionists a two-to-one lead. The polling occasionally shows slight improvements for Alex Salmond’s efforts only for them to melt away again within a week; finding a reliable trend has so far been like finding the holy grail for the nationalists.

Nevertheless, Cameron cannot afford to be complacent, and his New Year message that talked of more effort being put into winning the arguments of the heart as well as the mind (where there is general agreement that unionists are winning) was the right pitch. In this column over the coming months I shall look at some of the issues that the No and Yes campaigns face, including what options remain for Cameron and his party, but for all unionists the biggest danger at the moment is complacency and the possibility that they will take their collective eye of the ball.

The referendum – especially one against as wily a campaigner as Alex Salmond – is a long game, and long games require much deep thought and careful advance planning. There have to be no surprises for Cameron, by which I mean his strategists should have looked at all the possible issues and the various scenarios that they might present, and he should know when is the right time to say something and when it is best to say nothing – or leave the words to someone else, such as No campaign figurehead, Alistair Darling, the former Labour Chancellor.

The role of Scottish Party leader Ruth Davidson shall also be crucial, as will be that of Tom Strathclyde, who chairs the party’s commission on what further powers can be presented in future legislation, as Conservatives try to nail the devolution blancmange to the ground. Strathclyde’s commission is already well behind schedule: having meant to report last year, it is not expected to publish until shortly before the Scottish Conservative conference in March. One cannot help but think that Struan Stevenson MEP, with over forty-two consecutive years as an elected Conservative, would have offered a more dynamic Chairman to instil confidence and get results, but the appointment of Strathclyde suggests Cameron’s eye was on winning over English parliamentarians, who are more familiar with the former Conservative Leader of the House of Lords.

This herculean effort (there will be much gnashing of teeth) will be matched by a Labour Party discussion paper, while the Liberal Democrats did their policy work some two years ago. The drawing together of these ideas will present the possibility of some form of constitutional convention that could win much positive support in Scotland. But there is a danger, and it is one that has been apparent from the start when Tony Blair and Donald Dewar took the UK on our asymmetric devolution journey – namely, that a constitutional arrangement that is different for Wales, Northern Ireland and Scotland does not have any sense of permanence so long as it excludes the largest country in the union, England.

It is imperative that Strathclyde, Davidson and Cameron plot a set of proposals that give finality to constitutional debate for more than a generation. The constant chipping away at institutional structures and their imbued British character is as great a threat to the union as the referendum itself and must be brought to an end – otherwise we shall simply have more demands for change within another parliamentary term, and the expectation of a further referendum in the future. The SNP has already signalled that if it loses on 18 September it will plan for another vote in 2029. A long way off, certainly – but the intent is there and it should be the design of the unionists to slay the nationalist dragon altogether by not only winning the referendum, but also by putting the issue to bed in the minds of the British people by developing a Scottish Constitutional convention that blossoms into a debate and solution for the whole United Kingdom.

This opens up the possibility of also ending the constant rumbling about reform of the House of Lords by giving it a role across the UK, such as scrutinising new Bills in the devolved institutions, with local peers sitting in session at those institutions to hear representations and take evidence. They might also usefully review the comparative success of the legislative output since 1999 – something that Edinburgh and Cardiff show an inability to do. But developing these thoughts is for another time: my point is that Cameron could, if he is bold, actually take control of these issues and give leadership that would put the union at ease with itself. Surely that is an attractive goal?

It has already been forgotten that, as a result of the Scotland Act of 2012, the status quo will change irrespective of the referendum, with a new range of powers for Holyrood that has not yet been properly explained or had plans made by the SNP government for introduction in 2015. This is a serious oversight by the unionists who can at least point to their credibility in being willing to bring forward change by delivery of the latest act through cross-party agreement (it started out under the Labour Government and was delivered by the Conservative-Liberal Democrat Coalition). Further changes that raise the general levels of funding that devolved institutions manage, by way of greater variation in certain taxes and devolving others such as Air Passenger Duty, must be on the agenda with the aim of them taking more responsibility – but should also be balanced by looking again at the number of MPs that sit at Westminster: in other words the British dimension must be included.

It is this need to involve the English party – from cities to shires – that has been lacking in the Conservative approach, and may yet prove a trump card. Not because the English should have a say in how Scots vote, but because offering a UK-wide settlement will give the latent Scottish unionist majority (across all parties) the much-needed confidence that what is being offered has a degree of permanence.

The polls consistently show that Scots want more powers without being clear about what they want. (Terms such as Devo-Max, Devo Plus and Devo Extra are generally meaningless.) It is my view that this is because we Scots are always being told more sweeties will be handed out at the next confectioners down the road and we won’t need a trip to the dentists afterwards. This ‘spoiling’ of the Scottish electorate has to end.

It is time for David Cameron, as Prime Minister of the United Kingdom of Great Britain and Northern Ireland, to halt this teasing charade and bring some responsibility into Scottish constitutional politics by setting the United Kingdom’s parameters for the debate. This requires him to think about how England is governed and how English legislation is presented, scrutinised and passed. Only then will Scots see that what has been arranged for them has a rational sense for all British people and that asking for yet more – after any new settlement – will not be an option.

It is this English ambiguity that has fed the uncertainty surrounding unionism and allowed nationalists to keep sucking on their Edinburgh Rock. If, during this year’s debate, Cameron does not bring some certainty to the UK’s destiny Scots could easily vote No and then, after the referendum, form an orderly queue outside the constitutional sweetie shop. It is in that context Cameron must address the issue and in that spirit the question should be put on 18 September 2014.